Pump construction



Feb. 14, 1928.

F. J. HEIDEMAN y PUMP CONSTRUCTION Filed Sept. 28. 1925 Patented Feb.14, 1928.

UNITED STATES PATENT GFFICE.

FREDJ. HEIDEMAN, OF DETROIT, MICHIGAN, ASSIGNOR F NINEIY PER CENT TOTHOMAS C. WHITEHED, 0F RIVER ROUGE, MICHIGAN.

PUMP CONSTRUCTION.

Application filed September 28, '1925. Serial No. 59,125. l

This invention relates to pump constructions and finds particularutility in compressor pumps for use in connection with refrigeratingapparatus..`

An important object, of the 'present 1nvention is to provide a pumpconstruction so designed as to provide for' the segregation orseparation of the'refrigerant from the oil both in the crank case of thepump and 1n l0 the conduits of the refrigerating system.

The invention has also among its objects to simplify, render moreeilicient, and improve generally .devices of this' character, and theseas well as other objects, advan- 15 tages and novel details ofconstruction will be made more apparent as this description proceeds,especially when considered in connection with the accompanying drawings,wherein Fig. 1 is a vertical sectional view through a compressor pumpconstructed in accordance with my invention,

Fig. 2 is a top plan view thereof, and Fig. 3 is a fragmentary sectionalview 25 taken substantially on the plane indicated by line 3 3 in Fig.1.

In the drawings wherein like reference y characters indicate like parts,it will be noted that a pump is illustrated comprising a casing adaptedto contain a supply of lubricant and to enclose a fly wheel 11 mountedupon a crank shaft 12 journaled in .suitable bearings 13. l

Formed preferably, although not necessarily, integrally with casing 10is a cylinder .14 within which a piston 15 is reciprocably mounted. Thepiston is connected by means of a connecting rod 16 with the crank shaft12. The head 17 of cylinder 14 is provided with a suitable port 18 whichcommunicates with a conduit 19 by means of which the refrigerant or thefluld compressed in chamber 20 is conducted away. In the presentinstance conduit 19 is connected to a condenser.

Cylinder 14 has a chamber 21 formed at one side thereof to whichan'intake manifold 22 is secured, preferably by means of bolts 22engaging in threaded apertures formed in enlargements 23 in the wall ofchamber 21.

A tube or other conduit 24 is connected to the intake manifold 22 andconnects the manifold, when the invention is used as a part of arefrigerating apparatus, with the expansion coil.

Communication between intake manifold 22 and chamber 21 is establishedby means of an aperture 25 arranged preferably adjacent the lower sideof chamber 21, and communication between chamber 21 and chamber 20 ofcylinder 14 is established by means of a slot-like aperture 26 in thewall of cylinder 14, near the top of chamber 21 and spaced somewhatabove aperture 25. Consequently, on the down or suction stroke of piston15 the refrigerant or other gas will be drawn in from chamber 21 throughopening 26 into chamber 2() and upon a compression stroke will becompressed therein and forced out'through conduit 19 to the condenser.Obviously upon the downward or suction stroke of piston 15 the vacuumthus created in chamber 20 will cause a corresponding vacuum to obtainin chamber 21, thus drawing the contents of conduit 24 in through themanifold 22 and into chamber-2l. j

The wall of casing 10 adjacent the lower side of chamber 21 is formedwith an inclined restricted opening or passageway 27, the walls 28 ofchamber 21 adjacent thereto being inclined and merging into thepassageway. 27. This passageway affords communication between chamber 21and the interior of casing 10 wherein lubricating oil is contained. Thecasing 10 is provided, vadjacent passageway 27, with a downwardlyprojecting lug. or projection 29 forming` a battle wall which is spacedfrom the wall of casing 10 around lower end of passage 27 so as to formtherearound an inverted cup-like depression 30.

In practice a certain percent of the lubricant contained in casing 10becomes mixed or intermingles with the refrigerating medium and ispumped by the compressor through the refrigeratin system. While thiscannot be very easilay avoided it has been found to be unobjectionableand in fact desirable, if the amount of lubricant thus distributedaround through the refrigerating system can be curtailed or restricted.`If, as has heretofore been the practice, no means are provided forseparating this lubricant from the refrigeratin medium during operation,the lubricant will accumulate in the system, and particularly in theexpansion coil and prove objectionable.

In accordance with this present invention, however, the refrigerantcontaining a certain per cent of the lubricant which is drawn intochamber 21 upon the suction stroke of the pump is separated from thelubricant suspended therein in the chamber 2l. This occurs because ofthe greater specific gravity of the oil, which upon entering chamber 2lis not sufficiently suspended by the refrigerant to be drawn upwardlyand through aperture 26 into chamber 20, but on the other hand, falls inchamber 2l, flowing on to and being collected by the inclined walls 28and passing through passage 27 into crank case 10. This action isaccentuated by a miniature intermittent vacuum set up by the agitationof the oil in crank case 10 caused by rotation of iiy wheel l1. This flywheel rotates in the direction of the arrows in Fig. 1 and consequentlyagitates and displaces the oil in a similar circular movement, throwingthe same against baiiie wall 29 and across the mouth of recess 30. Thisaction of the oil creates in this recess and in the passage 27 theintermittent vacuum before referred to and assists in causing the oilcollected in the bottom of the chamber 21 to flow downwardly and intocrank case 10.

- In practice it has also been found that refrigerant,particularly-during an idle period of the refrigerating unit,accumulates in the crank case 10 and is confined therein because of itsbeing mixed or intermingled with the lubricant therein contained. Withthe present invention, this refrigerant is liberated when the compressoris again set into operation and is permitted to pass upwardly throughpassage 27, into chamber 21 and from there through port 26 to chamber20. The refrigerant is held captive by the lubricant in the form ofmolecules, which, during the initial operation of the refrigeratingunit, after a period of idleness, are broken up and the refrigerantthereby liberated, in which conditionit escapes upwardly through thepassage. 27 in the manner aforesaid. By making the passage way 27 of arestricted cross sectional area the oil is not carried upwardlytherethrough but is retarded by engagement vwith the wall of thepassageway, the greater specific gravity of theoil and the frictionalresistance set up by the wall of the passageway holding the oil withinthe crank case 10 while permitting an escape of the refrigerant.

From the foregoing it will be readily apparent that with a pumpconstructed in accordance with this invention, the greater part of thelubricant suspended in the refrigerant and being pumped through therefrigerating system is arrested as it enters chamber 2l at the pump andis separated from the 'refrigerant which is permitted to flow on to thepump cylinder, while the arrested lubricant is collected and conductedback into the crank case of the pump. Furthermore, the refrigeranttrapped by the lubricant in the crank case after a period of idleness oft-he refrigerating unit, is liberated and permitted to escape to jointhe refrigerant in circulation, while the lubricant which had entrappcdthe same is retained within the crank case.

Gbviously the objects and advantages of this invention will obtainirrespective of the character of the refrigerating apparatus or of theparticular design of the compressor pump, and consequently reservationis made to make such changes in the details of construction and in themanner of association as may come within the purview of the accompanyingclaims.

What I claim as my invention is:

1. The combination with a pump, of a lubricant arresting chamberinterposed between the intake manifold and pump cylinder thereof, thewall of said chamber being provided with a relatively restricted passageconnecting said chamber with the interior of the crank case of the pump,and a baffle arranged within said crank case adjacent the end of saidpassage, as and for the purpose set forth.

2. A pump formed with a crank case, a pump cylinder, and a chambercommunicating therewith and constituting part of an intake manifold,said chamber communicating with said crank case by means of apassageway, and a baiie wall adjacent the end of said passageway.

3. The combination with a pump having a crank case, cylinder and anintake manifold, of a lubricant arresting'chamber interposed between theintake manifold and pump cylinder, the bottom wall of said chamber beingprovided with a fluid collecting well having oppositely inclined wallscommunieating with a relatively restricted passageway connecting saidchamber with the interior of the crank case, for the purposes set forth.i

4. The combination with a pump provided with a crank case, cylinder, andintake manifold, of a lubricant arresting chamber interposed between theintake manifold and cylinder, the wall of said chamber being providedwith a relatively restricted passage connecting said chamber with'theinterior of said crank case, and a baiiie projecting downwardly vfromone wall of said crank case adjacent said passage forming an invertedcup-like depression, for thev purposes set forth.

5. The combination with a pum having a crank case, cylinder and an intae manifold, of a lubricant arresting chamber interposed between theintake manifold and the pump cylinder, and means for withdrawing thelubricant from the said lubricant arresting chamber, said meansincluding a passageway between the lubricant arresting chamber and thecrank case, a bale within the crank case, and means cooperating with thesaid baiiie for establishing an intermittent vacuum in the said passage.

6. The combination with a pump having a crank case, cylinder and anintake manifold, of a lubricant arresting chamber arranged entirelyabove the said crank case and interposed between the said intakemanifold and the pump cylinder, the said lubricant arresting chamberbeing provided with a depression on the inner face of its bottom wall,and

a passage extending from the base of the said depression to the crankcase opening into the crank case at a point adjacent the top thereof.

7. The combination with a pump, of a lubricant arresting chamberinterposed between the intake manifold and pump cylinder thereof, onewall of said chamber being provided with a relatively restrictedpassageway connecting said chamber with the interior of the crank case,and means upon one wall of the chamber and positioned adjacent one endof said passage for preventing the lubricant contained within said casefrom entering said chamber.

In testimony whereof I aix my signature.

FRED J. HEIDEMAN.

